Screen



May 29, 1934- A. c. DURDIN, .JR 1,960,303

SCREEN Filed Dec. 19, 1952 Wew @ATTORNEY INVENTOR.

Patented May 29, 1934 SCREEN Augustus C. Dui-din, Jr., Chicago, Ill., assigner to Chicago Pump Company, Chicago, Ill., a corporation of Illinois Application December 19, 1932, Serial No. 647,913

This invention relates to screens and has particular reference to screens adapted for screening sewage. The principal object of this invention is to provide a stationary self-cleaning straining wall of cylindrical form having circumferentially disposed slots therein through which the strained or screened liquid may flow to another place for subsequent treatment. Another object isto provide rotating cleaning means for the slots, whereby to free them of matter that would otherwise clog them and thereby interfere with the flow of the liquids therethrough. Another object is to provide novel means for clearing the slot cleaning means of accumulated matter whereby the l5 screen may always be maintained at its maximum e'iciency.

The invention consists in the several novel features hereinafter fully set forth and claimed.

The invention is clearly illustrated in the drawing accompanying this specification in which:

Fig. 1 is avertical section of a screen embodying la simple form of the present invention;

Fig. 2 is a horizontal section taken on the line 2 2 of Fig. 1; and

Fig. 3 is a detail fragmental sectional view, il-

' lustrating the construction of the straining wall.

Referring to said drawing, which illustrates one embodiment of the invention, the reference character 10 designates a channel or flume through 0 which sewage or other liquids for treatment is conveyed to the screen and this channel communicates through an opening 11 in its bottom with a duct or conduct 12 therebelow, through which the strained liquid is conveyed away for further treatment.

The screen is placed above the opening 11 and intercepts solids and other foreign matter which is incapable of flowing through the screen with the liquid. As shown a flange 13 surrounds the opening 11 and is bolted to the bottom of the channel 10 by bolts or cap screws 14. Extending up from said flange is a straining wall of cylindrical form, preferably composed of uprights 15` connected by spaced ring sections 16. Desirably the ange 13, uprights 15 and ring sections 16 are cast integral as a unit, although this is not essential to the invention, broadly considered, but it has its advantages in that it assures accuracy in machining and set up.

The spaced ring sections serve to intercept solids and other material incapable of-passing through the slots, and said ringI sections are inset with reference to the uprights, their ends 29 being oiset outwardly and directed to the uprights, and preferably spaced apart, thereby leaving free spaces or gaps 17 between the concentric parts of the ring sections, the purpose of which will appear later. When the ends' of the ring sections are spaced apart, uprights 15 bridge the gaps and rigidly connect the ends of the ring sections, thereby forming complete rings.

Upon the tops of the uprights, a flange 18 1s secured Aby studs and nuts 19 or otherwise, and. said flange supports a hollow head 20, to which is secured a reduction gear casing 21 of conventional construction above which is an electric motor 22.

A drive shaft 23 depends from the reduction gear and passes through bearings 24 mounted in the head 20, and upon said shaft are mounted the heads 25 that support the combs or toothed Scrapers. The heads are provided with a. hub 26 that is fastenedupon the drive shaft 23. The heads may take the form of upright bars having radial holes formed therein, to receive the teeth 75 or scraper blades 28 which are fastened in place in the heads by set screws 27. The teeth protrude from the heads and extend into or preferably through the slots between the ring sections and their extremities are adapted to co-operate with the inner edges of the uprights to comminute material that may be caught between them. The set screws 27 provide means whereby the teeth may be adjusted relative to the straining wall.

In operation, the shaft 23 is rotated and there- 85 with the heads are rotated'with the teeth traversing the slots and clearing them of Aany solid or semi-solid matter that may have collected therein. As the teeth pass the free spaces '17 between the ends of the arcuate portions of the ring sections, accumulated vmatter that they have picked up while passing through the slots, is free to fall away from the teeth whereby they are cleared of the material. Furthermore, the offset end portions 29 of the ring sections serve to strip accumulated material from the protruding ends of the teeth and pieces that are caught between the fingers and the edges 30 of the uprights are sheared or cut off thereby reducing such pieces to a size enabling the cut off pieces to pass through the slots along with the flow of the liquid. Large solids that accumulate are removed by any of the present day methods as is well understood.

I claim as new and desire to secure by Letters Patent:

1. A screen comprising in combination, a stationary straining wall composed of spaced ring sections, having gaps between their ends and supports bridging the gaps and rigidly connecting said ring sections and supporting them in spaced relation to leave slots therebetween, and a rotating toothed scraper having teeth traversing said slots and emerging in the gaps,

2. A screen comprising in combination a stationary straining wall composed of spaced ring sections, and supports connecting said ring sections and supporting them in spaced relation to leave slots therebetween, and a rotating toothed scraper having teeth traversing said slots and co-acting with said supports to comminute material caught between them.

3. A screen comprising in combination, a stationary straining wall composed of spaced ring sections having oi'set end portions, spaced apart to leave a gap therebetween, supports disposed at one side of the curved plane of the ring sections, one support bridging said gap and connecting the offset end parts thereof, and a rotating toothed scraper having teeth extending through and traversing the spaces between the ring sections, said offset end portions serving to rid the ends of the teeth of accumulated matter.

4. A screen comprising in combination a stationary straining wall composed of spaced ring sections having gaps between the ends thereof, uprights disposed at one side of the curved plane of the ring sections, said uprights bridging the gaps and supporting the ring sections in spaced relation to leave slots therebetween, and a rotating toothed scraper having teeth extending through and traversing said slots and emerging at said gaps.

5. A screen comprising in combination a stationary circumferentially slotted straining wall of cylindrical form, said Wall having abutments disposed outside the curved plane of the wall, and a rotating toothed scraper having rigid teeth traversing the slot-s and projecting beyond said curved wall and co-operating with said abutments of the wall to comminute material caught between the teeth and abutments.

6. A screen comprising in combination a stationary circumferentially slotted straining wall of cylindrical form, having supports at one side of the slotted portion of the wall, and a rotating toothed scraper having rigid teeth and traversing the slots and projecting beyond the wall, said teeth (zo-operating with the supports to comminute material caught between the teeth and the supports.

7. A screen comprising in combination a stationary circumferentially slotted straining wall of cylindrical form having a longitudinally extending gap along its length, and upright supports offset with respect to the slotted part of the wall and bridging the gap, anda rotating toothed scraper having rigid teeth that extend through and traverse the slots.

AUGUSTUS C.- DURDIN, JR. 

